A requirement exists for a simple reliable and compact conveyor with a variety of applications, which can be applied for example, as a grate stoker installed in furnaces having a limited height (particularly, in firetubes). Conventional grate stokers: chain grates, sprinkler stokers, overfeed, underfeed, and even vibrating stokers fail to meet this condition. In most cases there is also no possibility to change the profile and distribution of fuel and ash layer on the grate without manual interference.